diff --git a/tests/regression_tests/weightwindows/test.py b/tests/regression_tests/weightwindows/test.py
index a2708ac4bf..b1656e0e59 100644
--- a/tests/regression_tests/weightwindows/test.py
+++ b/tests/regression_tests/weightwindows/test.py
@@ -93,14 +93,14 @@ def model():
                                 None,
                                 10.0,
                                 e_bnds,
-                                max_lb_ratio=1.0)
+                                max_lower_bound_ratio=1.0)
 
     ww_p = openmc.WeightWindows(ww_mesh,
                                 ww_p_lower_bnds,
                                 None,
                                 10.0,
                                 e_bnds,
-                                max_lb_ratio=1.0)
+                                max_lower_bound_ratio=1.0)
 
     model.settings.weight_windows = [ww_n, ww_p]